I've had a look and I have the same connector with the rubber blank on so I don't know why they put the vac pipe on the manifold. The oiler seems to work fine how it's been set up so I'll leave it. No point mending it if it's not broke.
I've fitted mine the same as Curly but have run the oil tube on top of the swing arm, not underneath as recommended by scottoiler, to allow me to use a paddock stand. John
I cant fit a centre stand, mine came fitted with the arrow exhausts and you cant have a centre stand with them fitted.